Detection, quantification, isolation, and purification of target biomaterials such as viruses and biomacromolecules (e.g., including constituents or products of living cells, for example, proteins, carbohydrates, lipids, and nucleic acids) have long been objectives of investigators. Detection and quantification are important diagnostically, for example, as indicators of various physiological conditions such as diseases. Isolation and purification of biomacromolecules are important for therapeutic and in biomedical research. Biomacromolecules such as, for example, enzymes which are a special class of proteins capable of catalyzing chemical reactions are also useful industrially; enzymes have been isolated, purified, and then utilized for the production of sweeteners, antibiotics, and a variety of organic compounds such as ethanol, acetic acid, lysine, aspartic acid, and biologically useful products such as antibodies and steroids.
In their native state (i.e., in vivo), structures and corresponding biological activities of these biomacromolecules are maintained generally within fairly narrow ranges of pH and ionic strength. Consequently, any separation and purification operation must take such factors into account in order for the resultant, processed biomacromolecules to have potency.
Chromatographic separation and purification operations can be performed on biological product mixtures based on the interchange of a solute between a moving phase, which can be a gas or liquid, and a stationary phase. Separation of various solutes of the solution mixture is accomplished because of varying binding interactions of each solute with the stationary phase; stronger binding interactions generally result in longer retention times when subjected to the dissociation or displacement effects of a mobile phase compared to solutes which interact less strongly and, in this fashion, separation and purification can be effected. Column chromatography has been used to purify biological compositions; however, this technology is generally plagued by low throughput rates, channeling in the column packing, and/or high cost.
Polymeric resins are known for the separation and purification of various target compounds. For example, polymeric resins are used to purify or separate a target compound based on the presence of an ionic group, based on the size of the target compound, based on a hydrophobic interaction, based on an affinity interaction, or based on the formation of a covalent bond. Recently, ligand-functionalized substrates having such a polymeric coating on a substrate have been developed to aid in purification of biological compositions; for example, as disclosed in U.S. Pat. No. 8,377,672 B2 (Rasmussen et al.) and U.S. Pat. No. 8,435,776 B2 (Rasmussen et al.).